Aeroponic growing is distinct from other hydroponic or soil-less plant culture which include ebb and flow, pond, and aggregate growing methods. In the ebb and flow method, the roots are periodically submersed in liquid nutrients; in the pond culture method, the roots are suspended in a solution of liquid nutrients, which solution is generally oxygenated; and in the aggregate growing method, the liquid nutrients are supplied to plants in a non-soil containing aggregate. Because plants require oxygen to their roots, hydroponic methods are designed to allow both oxygen and liquid nutrient to sustain the plants. Aeroponics sprays the liquid containing nutrient solution on the plant roots. These roots are generally bare and suspended in the chamber where the nutrients are sprayed.
“Hydroponics” began in the 1850's, was commercialized in the 1920's, and used by the Army in WWII. It includes using water, sand, and aggregate cultures as the growth medium. Plants fully immersed in water grow less well due to lack of oxygen for their roots. Methods to supplement oxygen to roots include providing an intermittent flow of nutrient solution to supply the plants (NFT, or “Nutrient Film Technology”), aerating the nutrient solution, and spraying of nutrients on roots. The second is similar to the joint Cornell University, NYSEG (New York State Electric & Gas), and NYSERDA (NYS Energy Research and Development Authority) facility where ponds have oxygen injected into the nutrient solution. Some researchers at Cornell have sprayed roots with nutrient solutions. Visits to several facilities identified the drawbacks of NFT and pond systems, such as the large amounts of water required, the need for sophisticated light control and cooling systems, insect problems, and labor for transplanting the individual plants.
Aeroponic systems spray nutrient solution on the roots of plants intermittently and have been used mostly in plant research. There are several styles of aeroponic units growing vegetables at Disney World in Orlando, Fla. However, modifications need to be made to existing systems for cost efficient commercialization.